n 1871 Christina Rossetti contracted Graves' disease or exophthalmic bronchocele, an illness which would bring her on the verge of death. [see Marsh, 398]. She suffered from it until 1873 and it transformed her both mentally and physically. ("As regard appearance, she looked a 'total wreck' in William's words: her hair fell out, her skin discoloured, and her eyes bulged." (Marsh, 397.))
When she wrote Sing-Song in 1872 she was 42 years old. Having declined two marriage proposals out of religious reasons — by James Collinson in 1850 (because he reverted to Catholicism) and by James Bagot Cayley in 1866 (probably because he was an atheist) — she must have realised that all possibilities of marriage and thus having children were gone.

Therefore, Sing-Song marks a turning point in both her life and writing. Her life-threatening illness resulted in a look back on her life so far:
On the happy childhood she had spend with her brothers and sister in her grandfather's home Holmer Green. ("The melodious maternal speaking voice of the volume is that of the adult self 'mothering' the child within;. . ." (Marsh, 379.)).
Also at her longing for a husband and child, which is disguised in the dedication of the book to Cayley's nephew, and in her deep love for her brother William's children. (" . .her love was now directed towards William's children - 'my children, I may almost say, as none other can be so near to me." (cited from Marsh, 543.) Both Zaturenska and Marsh interpret Sing-Song as a guise for Rossetti's longing for a child of her own:

Christina was not well known for her love of children; but the baby to whom the Sing-Song volume was dedicated was the nephew of her beloved Cayley, and for a moment one likes to think she may have thought of herself as holding another baby of the same blood in her arms." (Zaturenska, 195-196.)
"The true inspiration of her nursery rhymes was surely the children she herself would now not have." (Marsh, 379.).

According to Jan Marsh, "this rediscovery of the child's viewpoint was necessary, valuable and even healing for Christina." [382] Throughout her life she had, as Dorothy Mermin points out, turned "rebellion and rage against herself" [79]. Or, as Anthony H. Harrison puts it, turned to "Self-loathing" [77]. He goes on to describe these feelings of dissatisfaction, when he specifies: "Like the other Pre-Raphaelite poets, she was acutely sensitive to life's inevitable disappointments and losses, as well as to her own unfulfillment" [189]. She had been deeply unhappy, because she loved both Collison and Cayley successively, but could not bring herself to marry somebody who did not share her religious beliefs. Jerome McGann names "sexual frustration" as the cause for this unhappiness [170].
But, with the self-healing process of writing Sing-Song, she said good-bye to that part of her life and left it behind.

She then turned almost exclusively to devotional writing. But it is not a simple deathwish she expresses in her devotional poems. (Sandra Gilbert and Susan Gubar criticize this attitude of Rossetti's, which they refer to as "the aesthetics of renunciation" : "Rossetti, banqueting on bitterness, must bury herself alive in a coffin of renunciation" [575]. It is the longing for a 'new life' in which she will have all the things she could not have in this life: love and fulfilment.